# Effects of low-versus high-volume high-intensity interval training on glycemic control and quality of life in obese women with type 2 diabetes. A randomized controlled trial

PMID: 37954548
Journal: Journal of exercise science and fitness
Published: 2023 Oct
Authors: Ahmad AM, Mahmoud AM, Serry ZH, Mohamed MM, Abd Elghaffar HA

## Question

Does low-volume HIIT differ from high-volume HIIT for glycemic control, lipids, blood pressure, adiposity, cardiorespiratory fitness, and health-related quality of life in obese women with type 2 diabetes?

## Summary

This randomized trial compared low-volume and high-volume treadmill HIIT with non-exercise care in obese women with type 2 diabetes. Both HIIT doses improved glycemic control, lipids, adiposity measures, systolic blood pressure, treadmill endurance, and quality of life versus control; the 4 x 4 min dose produced larger gains for glucose, triglycerides, LDL, and treadmill time, while the shorter 2 x 4 min dose produced several similar benefits with less time.

## Population

- Obese women with type 2 diabetes on oral medication.
- Sample size: 72
- Age: 36-55 years; group means about 42-43 years
- Sex: Women only
- Fitness level: Not reported as trained.
- Health status: Type 2 diabetes, obesity, without major complications or exercise contraindications.

## Methodology

- Randomized controlled parallel-group trial with low-volume HIIT, high-volume HIIT, and non-exercising control groups.
- 12 weeks
- Physiotherapy Department of Fayoum University Hospital, Egypt.
- Randomized and controlled study design.

## Protocol

- Low-volume treadmill HIIT.
- Modality: Treadmill walking/jogging.
- Work intervals: 2 x 4 min.
- Recovery: 3 min active recovery at 65-75% peak HR.
- Sets or repetitions: 2 intervals.
- Intensity: 85-90% peak HR.
- Session duration: 19 min.
- Frequency: 3 sessions/week.
- Program length: 12 weeks.
- Progression: Treadmill speed and incline adjusted to reach target HR.
- High-volume treadmill HIIT and non-exercise control.
- Modality: Treadmill walking/jogging for active comparator; usual care for control.
- Work intervals: 4 x 4 min for high-volume HIIT.
- Recovery: 3 x 3 min active recovery at 65-75% peak HR.
- Sets or repetitions: 4 intervals.
- Intensity: 85-90% peak HR.
- Session duration: 33 min for high-volume HIIT.
- Frequency: 3 sessions/week.
- Program length: 12 weeks.
- Progression: Treadmill speed and incline adjusted to reach target HR.

## Outcomes

### Glycemic control
Status: improved
Both HIIT groups improved HbA1c, FBG, and 2-hour postprandial glucose versus baseline and control, with larger improvements after high-volume HIIT.

Between-group post values p<0.001 for glucose measures; high-volume superior to low-volume p<0.05.

### Lipids
Status: improved
Both HIIT groups improved TC, TG, LDL, and HDL versus baseline/control; high-volume was superior for TG and LDL but not TC or HDL.

Reported p<0.05 for significant changes; TG and LDL favored high-volume.

### Blood pressure, adiposity, HRQoL
Status: improved
Low- and high-volume HIIT produced similar improvements in TC, HDL, SBP, DBP except low-volume DBP, BMI, waist measures, and SF-12 scores.

No significant low- vs high-volume difference for these outcomes; low-volume DBP p>0.05.

### Treadmill time to maximal exhaustion
Status: improved
Both HIIT groups improved fitness versus baseline/control; high-volume improved more than low-volume.

High-volume superiority p<0.05.

## Practical Insights

- A 2 x 4 min HIIT format may be a time-efficient clinical option when session time is a barrier.
- A 4 x 4 min format may be preferable when glycemic control and fitness are the main goals.
- Use screening and HR monitoring for people with diabetes.

## Limitations

- No direct VO2max measurement
- No double blinding
- Limited assessor blinding
- Women-only obese diabetes sample
- No dietary records
- Medication dosage not modeled
- Hormonal status not controlled

## Safety And Adherence

- No unintended effects or harms were reported during or following training in either HIIT group.
- Participants with complications or exercise contraindications were excluded.

## Original Sources

- [PubMed](https://pubmed.ncbi.nlm.nih.gov/37954548/) (pubmed)
- [DOI](https://doi.org/10.1016/j.jesf.2023.08.003) (doi)
- [PMC full text](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10632101/) (full text)

## Agent Guidance

Preserve the paper-level scope of this note. Do not generalize beyond the population, protocol, measured outcomes, and limitations above.